Method of manufacture of a ribbed pile

ABSTRACT

This low-cost, light-weight, high-strength, hollow cylindrical pile having longitudinal ribs is manufactured by rolling an elongated metal plate of predetermined width so as to produce spaced ridges thereon extending at a predetermined angle between lateral edges. The ridged metal plate is spirally wound so that the ridges register to produce longitudinally-extending ribs and the juxtaposed lateral edges are joined, preferably by welding, to form a continuous spiraled joint. When driven into a penetrable medium, the ribs provide directional control and means for joining adjacent piles into a unitary structure.

United States Patent 1 Otani June 19, 1973 METHOD OF MANUFACTURE OF A RIBBED PILE [76] Inventor: Akemasa Otani, 4, Z-chome,

Asakusa Hashiba-cho, Tokyo, Japan [22] Filed: June 7, 1971 [2]] Appl. No.: 150,661

Related US. Application Data [62] Division of Ser. No. 806,918, March 13, 1969, Pat.

[52] US. Cl. 29/477.3, 29/475, 72/197,

[51] Int. Cl B23k 31/02 [58] Field of Search 29/477.7, 477.3,

[56] References Cited UNITED STATES PATENTS 10/1859 Seymour 72/197 8/1865 Rinehart. 10/1909 Bell .1 72/197 1,324,714 12/1919 Allen 29/477.3 2,618,845 11/1952 Quarnstrom 3,487,537 l/l970 Lombardi 3,585,709 6/1971 Muller et a]. 29/47 1.1

Primary Examiner-J. Spencer Overholser Assistant Examiner-Richard Bernard Lazarus Attorney-Pendleton, Neuman, Williams & Anderson [57] ABSTRACT This low-cost, light'weight, high-strength, hollow cylindrical pile having longitudinal ribs is manufactured by rolling an elongated metal plate of predetermined width so as to produce spaced ridges thereon extending at a predetermined angle between lateral edges. The ridged metal plate is spirally wound so that the ridges register to produce longitudinally-extending ribs and the juxtaposed lateral edges are joined, preferably by welding, to form a continuous spiraled joint. When driven into a penetrable medium, the ribs provide directional control and means for joining adjacent piles into a unitary structure.

5 Claims, 8 Drawing Figures PATENTEU 3. 739.459

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AT TOR NEYJ PATENTED JUN 1 91973 SHEET 3 OF 3 INVENTOR ATTORNEY4 METHOD OF MANUFACTURE OF A RIBBED PILE limited to steel. Other suitable metals which can be mechanically worked economically, such as nickel, aluminum, copper, lead and various alloys, including chromium and nickel-containing ferrous alloys, and equivalents, may also be used, as those skilled in the metalworking art will recognized in the light of the present disclosure.

Steel tubing piles are driven into the earth to form a foundation, and therefore it is required that they be driven straight down. However, conventional spiral steel tubing piles, since they have been manufactured simply by spirally winding flat and plain steel strip and welding the adjacent edges thereof, are prevented frequently from being straight driven due to irregular earth pressure resistances, uneven driving, etc. Another disadvantage of such conventional spiral tubing piles is that they are deformed so as to be uneven in their resistance to pressure. Accordingly, wall thickness must be substantial, thus increasing material costs, manufacturing costs and weight.

To provide a spiral steel tubing pile wherein such disadvantages as above are eliminated, an object of the invention is to construct a strong spiral tubing wherein a plurality of radially projecting ridges or ribs are provided at regularly spaced apart positions about the periphery of steel tubing along the generatrices thereof, and to manufacture a pile therefrom in an easy, inexpensive and exact manner. The ribs are preferably disposed on the exterior surface of the tubing but may, alternatively or in addition, be disposed on the inner or interior surface.

In the spiral steel tubing pile according to the invention, the plurality of ribs extending along the generatrices serve as guiding means during the driving into the earth, so that the pile is always driven straight down and has no tendency to be deflected. Further, the pile is extremely rigid and strong by virtue of these ribs acting as reinforcing means, so that any torsional moment on such pile may be avoided even when subjected to irregular, uneven external forces. Thus, the pile according to the invention can be made from thinner sheet stock and will still be strong so as to maintain its normal configuration.

Moreover, the ribs are utilized as guiding means when a plurality of piles are driven in juxtaposed relation by engaging a rib of one of said piles with that of an adjacent one, and are also employed as means whereby adjacent piles may be welded together. Further, the pile of this invention can be easily and exactly manufactured by rolling the flat plates with a grooved roll.

The invention will be more clearly understood from the following detailed description of a specific embodiment thereof, said description beingread in conjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a spiral steel tubing pile of the present invention, sectioned at the center to show additional detail;

FIG. 2 is an enlarged sectional view on the line II in FIG. 1;

FIG. 3-1 shows a ridged plate from which the tubing pile is produced by spirally winding the same;

FIG. 3-II is an enlarged sectional view on the line II-II in FIG. 3-I;

FIG. 4 is a side elevation showing the tubing pile in a bent condition;

FIG. 5 is a plan view showing a plurality of the steel tubings of the present invention adjacently driven into position to form a pile wall;

FIG. 6 is a side elevational view of a roll apparatus illustrating the manufacture of ridged steel strip for the spiral steel tubing of the present invention; and

FIG. 7 is a sectional view on the line III-III in FIG. 6.

As shown in FIGS. 3-] and 3-H, a length of steel plate strip 1 of suitable constant width is provided on its outer surface 2 with a plurality of ridges or ribs 4 extending at a suitable inclination angle a to the opposite edges 3, 3' thereof and parallel with each other with regular pitch spacings S therebetween. According to said inclination angle, the length of ridged steel plate strip 1' is spirally wound, with the ridges being preferably disposed on the outside, to form a cylindrical tubing. After the formation of cylindrical tubing, adjacent sections of the ridged steel plate strip 1' are welded together in such manner that the ridges on said adjacent sections will be continuous in straight lines, thereby providing a ribbed spiral steel tubing 6.

This spiral tubing is optionally driven into the earth as a foundation pile. Since the spiral tubing foundation pile is so strong and tough, it can be bent into U-shape as shown in FIG. 4 without any crack or fracture at the bent portion. Such bent pile may be advantageously utilized as a sort of sheet pile.

FIG. 5 shows the present piles driven in juxtaposed relation. In this case, the ribs are utilized as guide means as well as welding means.

The elongate ridged steel plate strip can be easily and positively produced in continuous manner by a rolling machine. As shown in FIGS. 6 and 7, a roll 7 is produced with inclined or spiral grooves 8 on its outer peripheral surface, said grooves corresponding in their depth and pitch angle to the height and inclination angle a of ridges 4 which are to be formed on the elongated steel plate strip 1.

Q The flat steel plate strip is forced into the nip between said roll 7 and opposed roll 10 in the direction shown by arrow 9 in FIG. 7, and is pressed and rolled, whereby the ridged steel plate strip 1' may be readily produced. Rolls 11 and 12 are backup or supporting rolls for rolls 7 and 10, respectively. In this operation, thickness reduction is made from d in the plate 1 to d' in the plate I. By forming the section of each ridge 4 in trapezoidal shape and making the root portions thereof with curved surfaces 4', stress cracks or the like during the rolling can be eliminated. As described above, the ridged steel plate strip thus produced is then wound spirally and welded at the adjacent edges thereof to thereby obtain a ribbed spiral steel tubing.

From the above description it is apparent that the objects of the present invention have been achieved. Whileonly'one embodiment has been illustrated, many alternative modifications will be apparent from the above description to those skilled in the art. These and other alternatives are considered within the spirit and scope of the present invention, and coverage thereof is intended by this application.

What is claimed is:

1. A method of manufacturing ribbed metallic tubing pile having a plurality of continuous, spaced, upstanding ribs extending longitudinally along said pile, said method comprising the steps of:

a. providing an elongated flat strip of the metal of predetermined constant width defining two elongate, parallel lateral edges;

b. mechanically working said strip so as to integrally form on at least one surface thereof a plurality of spaced, upstanding parallel ridges of predetermined height, said ridges having end portions extending to each of said lateral edges of said strip and being disposed at an acute angle relative to said lateral edges of said strip;

c. spirally winding the resulting ridged strip so that the lateral edges are juxtaposed to form a continuous cylindrical tubing, the diameter of said continuous cylindrical tubing, the width of said strip and said acute angle being predetermined so that the end portion of each of said parallel ridges on one of said lateral edges aligns with the end portion of another of said parallel ridges on the other of said lateral edges, so as to form a plurality of longitudinal continuous spaced ribs; and

d. joining the juxtaposed lateral edges of the spirallywound ridged strip.

2. The method of claim 1 wherein the metal is steel and the juxtaposed lateral edges are joined by welding the same.

3. The method of claim 1 wherein the step of mechanically working said strip is carried out by feeding the strip into the nip between opposed rolls, at least one of said rolls being provided with recesses corresponding in their configuration and disposition to said ridges.

4. The method of claim 1 including the step of embedding the resultant tubing in a penetrable medium adjacent to like tubing so that ribs of each are in juxtaposed relationship.

5. The method of claim 4 including the step of welding together the juxtaposed ribs. 

1. A method of manufacturing ribbed metallic tubing pile having a plurality of continuous, spaced, upstanding ribs extending longitudinally along said pile, said method comprising the steps of: a. providing an elongated flat strip of the metal of predetermined constant width defining two elongate, parallel lateral edges; b. mechanically working said strip so as to integrally form on at least one surface thereof a plurality of spaced, upstanding parallel ridges of predetermined height, said ridges having end portions extending to each of said lateral edges of said strip and being disposed at an acute angle relative to said lateral edges of said strip; c. spirally winding the resulting ridged strip so that the lateral edges are juxtaposed to form a continuous cylindrical tubing, the diameter of said continuous cylindrical tubing, the width of said strip and said acute angle being predetermined so that the end portion of each of said parallel ridges on one of said lateral edges aligns with the end portion of another of said parallel ridges on the other of said lateral edges, so as to form a plurality of longitudinal continuous spaced ribs; and d. joining the juxtaposed lateral edges of the spirally-wound ridged strip.
 2. The method of claim 1 wherein the metal is steel and the juxtaposed lateral edges are joined by welding the same.
 3. The method of claim 1 wherein the step of mechanically working said strip is carried out by feeding the strip into the nip between opposed rolls, at least one of said rolls being provided with recesses corresponding in their configuration and disposition to said ridges.
 4. The method of claim 1 including the step of embedding the resultant tubing in a penetrable medium adjacent to like tubing so that ribs of each are in juxtaposed relationship.
 5. The method of claim 4 including the step of welding together the juxtaposed ribs. 